Although I don't have monster thighs (but they're decent, IMHO), I still prefere 1/8" drivetrains, because practice has shown that the 1/8" chainring will outlast several times the 3/32" chainring of similar size and equal material.
1/8" cogs also seem to last longer. This is harder for me to tell exactly, because I haven't paid as much attention as with the chainrings, but the ratio seems about the same.
I can say that a 1/8" chainring can probably outlive 3 3/32" chainrings subjected to the same force and stresses. This is purely my own experience. YMMV.
EDIT: and no, I don't have a clear scientific explanation for this. Such a huge difference is hard to explain.